cpi

ive got a 95 jimmy, had it about years, after a year it quit running diagnosed as injector, replaced it,running fine. during the diagnosis replaced filter, pump, tank. 6 months later running like crap, diagnosed injector regulator again. one half of the intake was discolered wet. symptoms of leaking regulator ok. 3 months later running bad again. in the last 4 months ive replaced the injector 3 times on a timer of 1 month. what im looking for is, if theres anything that i can check, or that causes this part to go bad. i called the dealership they said no, but that could just be so i bring it in for a diagosis. after i replace the part it runs great. 3 weeks rough 4th week i warranty the part replace it.

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posjimmy
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posjimmy-if indeed b-4 proceeding further a pressure gauge shows pressure bleedoff, I'd assume(probably) that the 'bleed-off' is in the injector area because you've had so much trouble here. Any codes? These 4.3 v-tecs were famous for EGR valve issues but that is another program. Back to this issue, if there is pressure bleed-off I'd pull the plenum back off, when removed I'd reach in the Jimmy(of course your battery is unhooked at this time), turn the key to the on position, then go back under the hood, watch the regulator as well as the lines that feed the injector REAL close as you reach over and hook up the neg(-) battery cable. This will cause the fuel pump to pressurize the system w/58-60 lbs. pressure which should reveal the source of your leak. Is the regulator GM or another company? I have had real good luck with is HELP/Motormite's regulator.. If you need I can get you a number on it tomorrow/whenever. If the injector has been replaced origionally maybe one of the line o-rings has developed a leak or possibly even one of the plastic lines has developed a crack. All this should be visable once apart(upper plenum off)and pressurize the system. Any one of the above issues would cause the inner plenum to get that 'washed' down look. If it is the regulator and you've had this much trouble I'd change brands, if possible. Also if it is the regulator it should show with the above procedure plus show fuel out the regulator 'weep' hole on the face of the regulator. good luck JP ps I'm assuming all else is hooked up correctly, ie-hoses around the plenem, plenum gasket is good/ no voids, sensors around intake all hooked back up, etc.

posjimmy wrote:

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jerry

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posjimmy

Reply to
posjimmy

pos jimmy-a couple of things. 1) have another set of eyes look at it as sometimes with me a different perspective makes all the difference in the world. 2) Double check your fuel pressures. Hook up pressure gauge, have someone key on the vehicle while watching the gauge, as the pump initially hums, you should show 58-60lbs of pressure for,the 1st 2 seconds or so. Then pressure normally should drop to 52-54 ish and hold. The pump will shut off until you crank engine. In your case, the pressure should drop(bleed off) if you do indeed have a leak. If all this happens, I'd switch to a Help/Motormite Regulator. Part number is 55162. No dealers in your area? Call 1-800-336-3575 ext.5330 and speak to Marty, he'll 'help' you! Tell him that I sent you his way. Again if all the above is ok, I'd look real close at ALL components within the plenum.. Often the leak could appear to be the regulator but....Those fuel feed lines(GM call em' nut unit)can fail,split.leak. But with your situation, I don't understand why all is good for 3 weeks or so..Strange, but there is a reason and you'll eventually find it if you don't go crazy first. Good luck. jp

posjimmy wrote:

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jerry

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